Official histories frequently have the advantage that the author has had access to archives, been allowed to interview subjects and use other primary sources closed to independent historians.
Such bias varies and some official histories have been called exercises in propaganda; in other cases the authors have retained a measure of independence.
[2] The modern form of official history began in the mid-nineteenth century in reports written as military guides for later officers.
The histories were detailed descriptions of events, not easy reading for a lay audience and left judgements to the discretion of a mainly professional readership.
None of the points of view to be served by the production of official history is immune to error, because work by a military historian might be fraudulent for personal or political reasons, distorting the record.
Populist history can dilute the story to the point of worthlessness and civilian academics can be prone to select facts and interpretations according to ideals, ideology and preconceived ideas.
The post-war Royal Air Force (RAF) was at risk of abolition and to justify its existence needed a function that could not be replicated by the army or navy.